Abstract
Purpose :
To evaluate the refractive outcomes of wavefront-guided (WFG) and wavefront-optimized (WFO) photorefractive keratectomy (PRK) and laser-assisted in situ keratomileusis (LASIK) in myopic eyes with moderate refractive cylinder.
Methods :
Subjects undergoing either PRK or LASIK for myopic astigmatism were randomized to either WFG or WFO treatment. WFG treatment surgeries were performed using the VISX CustomVue STAR S4 IR (Abbott Medical Optics) and WFO surgeries were done using Wavelight Allegretto Wave EyeQ (Alcon Surgical). The target refraction was emmetropia in all eyes. Eyes with preoperative refractive cylinder ranging from 1.00 to 2.75 diopters (D) were included in the data analysis. Refractive outcomes including astigmatic changes were assessed and compared among four treatment groups: WFG PRK, WFG LASIK, WFO PRK, and WFO LASIK groups. Vector analysis for refractive astigmatism was performed using Alpins method.
Results :
Data analysis included 117 eyes (40 WFG PRK, 25 WFG LASIK, 25 WFO PRK and 27 WFO LASIK) of 76 subjects (mean age 31.5 years ±7.3). Preoperatively, there were no significant differences among treatment groups in either refractive sphere (p=0.45), cylinder (p=0.69) or spherical equivalent (p=0.48). At 6 months postoperatively, there were no significant differences among groups in terms of eyes achieving uncorrected distance visual acuity of 20/20 or better (100% WFG PRK, 100% WFG LASIK, 96.0% WFO PRK, and 95.7% WFO LASIK, p=0.48); spherical equivalent within ±0.50 D of emmetropia (91.2% WFG PRK, 83.3% WFG LASIK, 88.0% WFO PRK, and 100% WFO LASIK, p=0.25); refractive astigmatism (non-vector) ≤0.50 D (94.1% WFG PRK, 87.5% WFG LASIK, 84.0% WFO PRK, and 100% WFO LASIK, p=0.19). Refractive astigmatism corrections were also comparable among treatment groups in terms of magnitude of error (-0.07 D WFG PRK, 0.00 D WFG LASIK, -0.02 D WFO PRK, and 0.04 D WFO LASIK, p=0.53); angle of error within ±15 degrees (100% WFG PRK, 95.8% WFG LASIK, 88.0% WFO PRK, and 100% WFO LASIK, p=0.08) and correction index (0.94 WFG PRK, 1.01 WFG LASIK, 1.02 WFO PRK, and 1.03 WFO LASIK, p=0.39).
Conclusions :
Wavefront-guided and wavefront-optimized PRK and LASIK were effective in treating myopic eyes with moderate refractive cylinder. Astigmatic changes induced by refractive surgery using either laser platforms were comparable.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.